Legacy access control systems have typically made use of a credential carried by the end user, a reader mounted at or near the access point to be secured, a server running access control software (the head end) and one or more door controllers mounted at or near the door to be controlled. In the case that connectivity between the door controller and the head end server is lost, these controllers contain a copy of the access database (credential list) and are capable of controlling the door or doors to which they are assigned.
Another approach for legacy access control systems makes use of RFID enabled battery powered locks mounted at each door to be secured. In the case of such a lock, an onboard database contains a credential list indicating who is allowed access, and at what times. Further, these lock databases often contain other data and information that we would like to synchronize with the head end access server. Examples of such information include things like access audit trails and the state of the battery charge in the lock. Since these locks often have no connection to the host they are considered to be “offline” locks. For an offline lock, a major challenge for the system designer is maintaining synchronization between the lock database (credential list) and the credential list maintained by the head end server. Additionally, when a particular lock has accumulated information that the system administrator should know, there can be delays in getting this information back to the head end server (access management system) so that the system administrator has visibility to it. Therefore, it is desirable to have improvements in entry access control to address the aforementioned issues.